Hello. I rode a hilly Sportive last Sunday and the Elevation Gain figure shown on TR is vastly different to that shown in Garmin Connect and Strava. See the attached screenshots. Any ideas? Thanks.
Is this related?
There are 2 methods of calculating elevation gain - barometric altimeter, and GPS elevation.
GPS elevation is “on average” correct, but very “noisy” - you can ride along a level road, and it will report +1 meter, -1 meter, +2 meters, etc. leading to an overestimate of elevation gained.
Barometric altimeters are very good at reporting CHANGES in elevation. However, over the course of a very long (7hrs) ride like that, changes in ambient air pressure can lead to errors.
GC and Strava both use their underlying mapping information to correct barometric elevation, while TR just uses the raw barometric data.
don’t think that is true, the last I checked Strava will use the bike computer’s elevation if it has a barometric altimeter. Looking at a few rides from this year, elevation in Strava matches Garmin Connect. For example:
On Garmin Connect and Strava, I can click a link on the ride page and it will correct elevation. For example on Strava: